So who thinks this is a good idea?

Sorry...terrible idea that MANY people might want, but FEW will actually find useful. As already said, the ramps will get bent. I'll add that the tracks will also get bent or out of shape. The tracks will get dirty and won't slide as good. The tail gate will get bent or broke; cables will break and damage the tailgate. Some kid will load his 4-wheeler, tumble off and get hurt, then sue Chrysler. And 10 years down the road, you'll see a used truck on the lot that's been traded in without the ramps because the original owner bent them.